Chinese President Xi Jinping is in Hong Kong this weekend to celebrate the 20th anniversary of the Sino-British Joint Declaration, which returned Hong Kong – Britain’s last major colony – to China on July 1, 1997.

“In the 20 years since Hong Kong was returned to the motherland, the success of ‘one country, two systems’ is recognized by the whole world,” Xi said in a speech today.

The system was put in place to maintain Hong Kong’s capitalist economy and the civil liberties it enjoyed under British rule.

Carole Petersen, a professor at the William S. Richardson School of Law at the University of Hawaii called Hong Kong home during that transition. She describes the handover as “a mix of somewhat fear, but also cautious optimism.”

“[The joint declaration] basically said the local Hong Kong government would have authority over virtually everything other than foreign affairs and defense,” Petersen says. “People were looking forward to what I call a sort of form of internal self determination – they would be part of the People’s Republic of China, but they would have the right to govern themselves largely.”

Yet, the generation that has grown up in Hong Kong during the past two decades under the promise of greater autonomy, has become somewhat disenchanted with the idea of “one country, two systems.”

“There’s a lot of fear in Hong Kong right now and a lot of pessimism,” Petersen says. “In the first initial years after the handover, I do think the Chinese government did a pretty good job of not interfering. The clash started with people’s demand for local democracy.”

The Sino-British Joint Declaration promised that Hong Kong could move gradually toward electing its own chief executive, however that has yet to happen.

“Every time they try to move in that direction, the Chinese government finds a reason to stop it,” Petersen says.

“Ever since then, we have seen Beijing interfere more and more,” Petersen says. “Every time Beijing interferes in the Hong Kong legal system or the Hong Kong local government, it actually has an effect that Beijing doesn’t want, which is it fuels the beginnings of an independence movement, which never existed before in Hong Kong.”

She says that “one country, two systems” remains unfinished business and says she was encouraged by Xi’s statement during the anniversary celebrations that he anticipates it to continue. Many observers have worried that China might put an end to the system and fully integrate Hong Kong into China.

“I think it’s the best thing we can get for Hong Kong. I don’t think the independence movement has a chance,” Petersen says. “China will fight to keep Hong Kong and China has massive military force.

I think the history books are not written yet – we still have 30 years to go in the initial 50 year promise, so let’s see how it happens.”